1. Field of the Invention
This invention relates to the recognition and recovery of noble metals and, more particularly, to the remelting of materials to allow certain metals, such as noble metals and rare earths, which may not otherwise be recognized, to be recognized and to be recovered.
2. Description of the Prior Art
Prior to the development of the apparatus and method developed by the present inventor as found in his prior U.S. Pat. No. 5,142,549, dated Aug. 25, 1992, and U.S. Pat. No. 5,263,044, dated Nov. 16, 1993, there had been no satisfactory way, either in terms of apparatus or method, of recovering certain metals, such as noble metals, in substantial quantities from certain types of ores, ore concentrates, anode mud, slag, and the like. The primary reason for this has been that the noble metals cannot be recognized.
It has been determined that noble metals may be unrecognizable in certain clusters. The clusters may be in primary ores or in the product of smelting processes or other processes from which certain types of metals are typically recovered, such as the processing of copper ores, iron ores, and the like.
While the chemical composition of the clusters is neither fully understood nor known, it is now recognized, primarily through the efforts and by means of the apparatus and method herein disclosed, that the unrecognizable metals, especially noble metals and rare earths, in the clusters may be freed from the clusters and may thus be either presented in the form of free atoms of the metals or may be alloyed with other metals. In both situations, the metals may be recognized and accordingly may be recovered through conventional recovery techniques.
The above referenced patents utilize an electron beam furnace to break down the clusters in order to recognize the noble metals in the clusters. Once the metals are able to be recognized, they may then be recovered by well known methods and apparatus.
The apparatus of the present invention utilizes a dc electric arc furnace and different procedures than the noted patents to break down the clusters in order to allow the noble metals to be recognized and thus recovered.